Delay action fuse



@CL 25, 1949. B. J, WILSQN ET AL 2,485,949

DELAY ACTION FUSEV Filed July 18, 1945 2 Sheets-Sheet 1 E] Enjamn J Wilsnn UME-MET ma? myfxmu c, 25, 1949. B. J. WILSON ET AL,

DELAY ACTION FUSE 2 Sheets-Sheet 2 Filed July 18, 1945 4 5 2 a. .fw wr N M w n 8 W (f n R r/ m nih f/ /////////l////////// a uert/RWA' Benjamn fl 'VX/"115 Em moz/nanfa Patented Oct. 25, 1949 DELAY ACTION FUSE Oreland, and John E. Stringer, Philadelphia, Pa., assignors to the United States of America as represented by the Benjamin J. Wilson,

Secretary of War Application July 18, 1945, Serial No. 605,704

3 Claims. 1 This invention relates to improved delay action type fuze to be used for detonating explosive charges and which is suitable for use in detonating submerged charges at a predetermined, future time.

More particularly, it is an aim of the invention to provide a novel construction of fuze, which is entirely of a mechanical construction and which includes a time measuring mechanism, such as a watch or clock movement, capable of being readily set and wound from the exterior of the fuze housing; which is provided with means to provide precision setting of the time mechanism, and which is further constructed so that the mechanism is protected from the effects of strong magnetic fields.

Delay action fuzes now used employ a chemical action for detonating the fuze at a predetermined future time, which chemical is extremely sensitive to variations of temperature, so that the exact time of detonation of the fuze cannot be exactly predetermined. It is therefore a primary object of the present invention to overcome this disadvantage by providing a mechanical fuze capable of being accurately set, and equipped with time measuring means which will function accurately to detonate the fuze at the desired future time, and which is not subject to variation due to changes of temperature.

Still another object of the invention is to provide a fuze, of the above described character, capable of being equipped with an inexpensive watch movement which is rugged and durable, which will minimize the possibility of failure to function, and which will enable the fuze to be accurately set to function at the desired time.

A further object of the invention is to provide a fuse having a safety means interposed in the path of the projected movement of the firing pin, which will prevent the functioning of the firing pin until said means is moved to a fuse arming, retracted position, and which will be held by the firing pin, to prevent retraction of said means, should the firing pin be prematurely released from a cocked position.

Another object of the invention is to provide a fuse having a window portion through which the setting of the time mechanism is clearly visible and also through which the position of a movable safety member can be seen.

Other objects and advantages of the invention will hereinafter become more fully apparent from the following description of the drawings, which illustrate a preferred embodiment of the invention, and wherein:

Figure 1 is a top plan view, partly in section, of a time delay fuse constructed in accordance with the invention;

Figure 2 is a view similar to Fig. l but showing the fuse parts in released positions;

Figure 3 is a cross sectional View taken substantially along the plane of the line 3-3 of Fig. 1;

Figure 4 is a cross sectional view taken substantially along the plane of the line 4-4 of Fig. 2; and

Figure 5 is a cross sectional view taken substantially along the plane of the line 5--5 of Fig. 1.

Referring more particularly to the drawings, wherein like reference characters designate like or corresponding parts throughout the several views, the fuze includes a fuze housing, designated generally 1, including a body portion 8, which is preferably formed of metal, and a transparent top wall or cover 9, which is preferably formed of a plastic. Cover 9 is detachably secured to the upper surface of the body 8 and along the edges thereof by means of a plurality of screw fastenings Ill, and a sealing gasket II is interposed between the parts 8 and 9 to provide a watertight connection. The housing 8 also includes a detachable bottom portion I2 which is secured to the opposite side or face of the body 8 by means of additional fastenin'gs Il). The bottom wall I2 includes an inner ply I3 of any suitable sealing material such as a plastic which forms a liquid-tight seal between the parts 8 and I2. The back cover I2 is formed of iron, which, due to its close proximity of the balance wheell of the time mechanism, not shown, reduces magnetic intensities sufficiently so that they do not aiect the accuracy of the time mechanism. l

The body 8 is provided with a bottom cavity I4 which is adapte-d to contain the time measuring mechanism I 4', the mechanism therein being not shown, and which, as previously mentioned, preferably consists of a watch movement of simple inexpensive construction which will be rugged, durable :and eicient in operation. The time measuring mechanism I4' includes a setting stem I5 which is provided with a knurled outer end IG which extends outwardly through an opening I1 in the bottom wall I2, I3. The opening I'I is in.- ternally threaded to receive a cap I8 in which the knurled end I6 is normally contained. The time measuring mechanism is also provided with a winding stem, not shown, which similarly extends through the wall I2, I3 and which is also enclosed Within a cap, corresponding to cap I8.

The upper part of the housing body 8 is provided with a cavity |9 containing a circular recessed portion and in which is rotatably mounted `a member 2|. The member 2| includes :a bottom portion 22 having an upstanding annular w-all 23 which is provided with an -upwardly opening notch 24. A shaft or arbor 25 extends upwardly through 'the :time mechanism |4' and is concenj. tric with the bottom 22. The shaft or arbor 25 is driven by the time measuring mechanism I4", ina conventional manner, to make one revolution each hour. A minute hand 26 is keyed to the upper end of the arbor 25 so as to rotate in the annular walled member 2|. The annular walled member 2| is also connected to the time measuring mechanism |4' in a conventional manner as in the case of the ordinary hour hand of a watch or clock and driven at a speed of one complete revolution in a period of twelve hours.

Referring to Fig. 2, the body portion 8 along one side thereof is provided with a fbore 0r barrel 21 having an open internally threaded end 28 which opens outwardly of one side of body 8 and which .is vadapted to be closed by means of a conventional percussion cap base or primer hold-er 29, which is recessed to contain a primer or percussion cap 30, the head of which is disposed at the inner end of the base 29 and within the barrel 21|. A ri-ng pin, designated generally 3|, is slidably mounted in the barrel 21 and is spring urged towards :the percussion cap 3U by an expansion spring .32, one end of which abuts against `the rear end of the firing lpin 3|, and the opposite end of which bears against the closed end of the .barrel 21. with a recessed .intermediate -portion 33 the rear end of which is defined by an annular cam sul"- face 534. lThe ring pin 3| iis provided with a restricted, lpointed projection 35 v:at its forward end which is adapted to strike and .de-tonate the percussion cap v3|) when the firing pin is moved from a cocked position, as seen .in Fig. l, toward a Iprojected position, -as seen in Fig. 2, by its spring 3'2. Referring to Fig. 3, the housing 1 is provided with upwardly extending bore 36 which extends through and slightly beyond the barrel 21, adjacent its open end 2B.. Bore 36 has ian outwardly opening end which is .formed by the bottom wall 12, "and which is internally threaded to receive a stuiling Ibox 31 which is provided with an inner., restricted threaded bore portion 38 and an outer .threaded bore portion 39. A bushing member 40, orrning a part of stuing box 31, threadedly engages bore portion 39. A .safety vstop member 4| is slidably mounted inthe bore '35 and is provided Y with a Stem 42, which extends from the outer end thereof through the bores 38 4and 39 and which slidably and turnably engages the bushing 4D. The stem 42 is 'provided with ya knurled knob 43 on its outer `end by means of which the stopmember 4| can'be `projected and retracted within the bore 36, relatively to the barrel 21. The `stem 42 is provided with axed v'threaded collar 4'4 which is engaged with the 'threaded bore 33, when the stop 4'l is in ra retracted position, by rotating the knurled'knob 43. lt will be readily apparent that the stop 4i when iri an operative position, as seen in Fig. 3, functions to retain the `fuze 6 disarmed Iby being ldisposed inthe :path of movement of the ilring pin .3l and between 'the firing vpin and the primer y30., and thereby prevents detona'tion of the primer '30 until the stop 4| has been retracted. 'Stop '41 'is provided with a keyway 41a which cooperates with a key pin 4 lb so as to .align a transverse opening "45 to receive projection '35 4if the The iiring pin 3| is provided firing pin 3| is inadvertently released from its cocked position prematurely. It will be readily apparent that if the projection 35 engages the opening 45 it will prevent the stop 4| from Ibeing retracted to yarm fuze 6, to thereby indicate that the fuze parts have been inadvertently released and that the fuze is not capable of bein-g used until the rin'g pin .has been recocked, .as will be described.

The inner side of the barrel 21, as seen in Fi-gs. 1 and 2, is -provided with a slot 46 which o-pens 'into the upper chamber or cavity I9. A scar 41 is pivotally mounted -at one end thereof by means of a pin 48, which extends into the body 8, within the chamber L9. The sear 41 is provided with a laterally onset intermediate portion which extends through the slot 46 and which includes an inclined shoulder or face 45 which bears flush against the cam surface 34, when the sear 41 is in an operative position, `as seen in Fig. 1. An arm 59 is pivotally mounted .by 4means of a pin 5|, at one of its ends, to the free vend of the soar 41. As best seen in Fig. 2, the `ar-m 50 .is progided with :a notch 52 at its 4free end, which --opens outwardly of said end and laterally from the inner edge of the arm 50 for a purpose which will hereinafter be described.

A -post 53 is anchored in the body `8 and extends upwardly there-from into the chamber i9. A detent lever 54 is rotatably connected at one end thereof to the post 53 and is provided with :an arcuately shaped shank. The -detent 54, adjacent itsjopposite, free end, normally engages in a :bifurcated guide 55 which is anchored to :the `bottom of the .chamber |9. The .-free end of the detent 54, beyond the .guide 55 is provided with a struck-out, downwardly projecting tongue 56, as best .seen in Figs. 4 and 5. The pivotally mounted lend of the detent 354 is laterally enlarged and. as best seen in Fig. 5, is provided with la ydownwardly extending lug 51 on one side of 'DOSt 53 and a downwardly extending trip arm 58 on the other .side of the post 53. A torsional spring 59 vis wound around and anchored to the post '53 and .has one end thereof engaging against the outer edge of the detent 54 .for urging the de- .tent 54 to .rotate in .a clockwise direction about 'thepost 53.

One side edge of the body 8 is Aprovided with an internally threaded bore 5U which communicates with a channel 6| which 'is formed in the body 8 and which opens upwardly into the Ichamber l'9. A stufiing box 62 is in threaded .engagement with bore 50 and a `stem '63 turnably engages the stuffing box 32 and fis provided with a knur'led knob 64 at its outer end. Stem 53 is provided 'with an integral threaded extension "65, on its `inner end, which is disposed in the upwardly opening channel 5|. A split washer 6'3 retains the stem 63 .in position `relative to the channel 6|, as more clearly shown `in Figure 4.

As best seen in Fig.. 4, a stop 6'6 provided with a restricted depending section 51 which is loosely disposed in the channel V6| and which is ,provided with a threaded 'bore which engages the threaded portion 65 for reciprocating the extension 61 Within the channel 51 Iwhen stem '63 and the threaded extension 65 are rotated. Stop member 66 is disposed in the chamber IB and 'is positioned for movement toward and away from the arm 5i) from an operative position, .as .seen in Fig. 1, to an inoperative position, as seen in Fig. .2. As best seen in Figs. l1 -and .2, stop B6 is .provided with an arm `68 which is fixed thereto `and which projects toward the center of the .fuse Ii and which is disposed substantially parallel to the stem 63 and above the arm 50.

A plate 69 is secured by means of fastening 10 to the bed of the chamber |9 and is provided with an opening 1| which surrounds the annular wall 23. The upper surface of the plate 69, around the opening 1| thereof, is suitably inscribed with circumferentially spaced markings and numerals from "1 to "11 arranged therearound in numerical order in a counterclockwise direction so that the markings and numerals are spaced equal distances apart except for the space between numerals r1 and 11, the distance between which numerals is twice the distance between any of the other two numerals. Between the numerals 1 and 11, the plate 6,9 has inscribed thereon anrin-V wardly directed arrowhead and the indicia fire The minute hand 26 is preferably coated with a radium substance and the disc or bottom portion 22 is provided with a dot 12 of the same material.

In order to set the fuse 6, preparatory to firing, firing pin 3| is retracted to its position of Fig. 1 and is engaged and held in a cocked position by the shoulder 49 of the sear 41. The notch 52 of arm 5|) pivoted on the sear 41 engages post 53 for holding the sear 41 of the firing pin in an engaging position. When detent 54 is disposed, as seen in Fig. 1, with its free end in the guide 55, the lug 51 engages behind the bill, formed by the notch 52, and positively retains said notch in engagement with post 53. The stop member 4| being advanced into obstructing relationship to the barrel 21, as seen in Fig. 3, forms one part of the safety means to prevent full release of the firing pin 3|, and a second part of this safety means is afforded by moving the stop member 66 forwardly and into engagement with the outer edge of the arm 50 to provide an additional means for preventing the notch 52 from being disengaged from the post 53. With the stop member 66 thus disposed, as seen in Fig. 1, the arm or extension 68 is bearing against the outer edge of the enlarged end of the detent 54 and against an edge of Sear trip 58 to retain the detent 54 in a fully retracted position, as seen in Fig. 1. When the fuse parts, previously described, are thus disposed, the fuse is in a safe or disarmed position, and while thus disposed the knurled knob I6 may be rotated for setting the hour member 2| and the minute hand 26, which will cause the fuse 6 to function at any desired future time up to approximately 11% hours after the time that the fuse 6 is set. After thus setting the mechanism in the conventional manner, said mechanism is wound in a conventional manner. The knob 64 is then rotated to retract the stop member 66 and its arm 68 out of engagement with the arm 5D and the detent 54, respectively. This movement of knob 64 actuates means, not shown, which is in engagement with the time mechanism to release it to cause the hour member 2| and minute hand 26 to begin to revolve, both in a clockwise direction. When the stop member 66 is fully retracted from its position of Figure 1 to its position in Figure 2, it will have completely disengaged itself from the arm 59 and the detent 54. This will release the detent 54 to permit said detent to swing in a clockwise direction a slight distance until the tongue 56 at the free end thereof is bearing against the annular wall 23, against which it lies as the hour member 2| revolves. The Wall 23 acts as a stop for holding the detent 54 in a retracted position until such time as the notch 24 moves into registry with tongue 56. Notch 24 is sized to permit the passage therethrough of the tongue 56 for releasing the detent 54 to detonate the fuse 6, as will presently be described. After the time measuring mechanism is set and the stop 66 is retracted to its position of Fig. 2, if there has been no movement of the scar 41, and assuming that the charge, not shown, to be detonated by the fuse is attached to the nipple and threaded outer portion of the primer base 29, the knurled knob 43 is pulled downwardly or outwardly to retract the stop 4| out of obstructing relationship to the barrel 21; and to insure that the stop 4| will remain in its retracted position, knurled knob 43 is rotated to cause the collar 44 to threadedly engage the threaded portion 38. With the parts thus disposed, the fuse 6 is ready to be detonatedV when .thehour member 2| has revolved in a clockwise direction sufficiently to bring the radium dot 12 into alignment with the arrowhead associated with the indicia re." When the radium dot 12 is thus disposed, the minute hand 26 will also be in alignment with said parts and the notch 24 will be approximately in the position as seen in Fig. 2, in which the parts 2| and 26 are shown a few moments after the release of the firing pin 3|. Thus it will be readily apparent that the minute hand 26 provides means for accurately setting the hour member 2|. The parts of the time mechanism are illustrated in. Fig. 1, with the parts disposed when said parts still have approximately an operating time of 55 minutes before release of the firing pin 3|. At the instant that the minute hand 26 and the dot 12 are aligned with the arrowhead, the notch 24 is disposed to permit the tongue 56 to pass therethrough, thus releasing the detent 54 to be moved by its spring 59 in a clockwise direction to the position of Fig. 2. The clockwise movement of the detent 54 will cause the lug 51 to move out of engagement with the outer edge of the arm 5U. Immediately after the lug 51 is moved out of engagement with the outer edge of the arm 50, the sear release detent portion 58 strikes the inner edge of the arm 50, to positively kick the notch 52 out of engagement with the post 53 to thereby release the sear 41. The Sear 41 is rocked in a clockwise direction, from its position of Fig. 1 to its position of Fig. 2, by the camming action of the coacting cam surfaces 34 and 49, due to the pressure exerted by the firing pin spring 32, to thus release the ring pin 3|, which is then spring-biased forward by spring 32 to strike and detonate percussion cap 30 for setting off the explosive charge attached to the outer end of the primer base 29.

All of the moving parts which project from the housing 1 are rendered liquid-tight by means of packing, and the joints of the housing parts are provided with liquid-tight sealing gaskets so that the fuse can function while in a submerged position and, due to the transparent top wall or cover 9, the operator is enabled to set the fuse 6, while it is in a submerged position, by viewing the position of the fuse parts through the window thus alforded.

Various modifications and changes are contemplated and may obviously be resorted to without departing from the spirit and scope of the invention as hereinafter defined by the appended claims, as only a preferred embodiment of the invention has been disclosed.

We claim:

1. A delay action fuze comprising a housing adapted to receive a time measuring mechanism therein, a part adapted to be driven by the time measuring mechanism, a detent disengageably amiamo 7 .by said part, -ra spring pressed -ring pin, and asear meansengaging and -holding the firing `pin .in a retracted, cocked position, said sear means netach'ably engaging the detentzand -being releas- .fazblyheld engagement with the firing pin thereby, "said detent having Aa lug bearing :against the sear fmeans for retaining .it in an operative Aposition rin engagement with 'the :firing ipin, said .ing being movable out of Iengagement with the VSear means :by the .movement of the detent vto a frelease'd position, .and a tongue :on the detent Vdis- `.posed to .engage tand trip the rsear means Itoward areleased position, when the detent is released.

.A -delay faction fuze comprising a housing adapted "to receive a time .measuring mechanism therein, .a .rotatable annular `Wall adapted to be itl-riveli .by the time mechanism, a pivotally mounted detent fhaving a free end vspring biased .into 'engagement With the Wall, 'La spring projected .firing pin, :a sear .means pivotally mounted at one Di? its ends and having a yportion engaging and holding the lring pin in a retracted, cocked position said Sear means having a free end portion rpivotally supporting fan arm engaging the Idetent 'for holding the sear means .in engagement with the 'firing `p'in, said annular Wall having :a notch 'for Ipassage :of fthe detent free end When the Wall is ^in one position, said detent, when released by its free =end thereof passing through the notch, fleeing spring biased 'to a position to release said arm of the sear means, fand said sear .means and ming pin having -co-acting cam surfaces for fcamming the ysear means Aout lof the path `of the :irin'g pin, 'and said detent having -fa lug vfor en- ;gaging-thexfree'end portionfof said arm Vand which `is movable out of engagement 'therewith when ythe detent is `'released by the annular wall, 'and a tongue on 'the detent for tripping said arm to in- 'sure release lof .said .'sear means.

3. A delay action fuze `comprising a housing adapted to receive `a time measuring mechanism Itherein, a rota-table annu-lar wall adapted to be 'driven by the time mechanism, a vpivotally mounted detent having a free end spring biased into engagement with the wall, a spring ,projected firiin-g pin, a searmeans pivotal'ly mounted at one of ,its ends 4and having agportion engaging 'and holdi8 ting the ring :pin in .a retracted, cocked position, said sear means having a free end portion pivotnlly supporting van `arm engaging the detent for holding the .sear means in yengagement with ythe .firing pin, fsaid annular Wall having a notch for passage `of the detent free end, when the Wallis .in one posi-tion, said lfdetent, when released by its .freeend thereof ,passing through the notch, being spring :biased -to .a 'position -to release said arm of 'the sear means, and said ASear means and firing pin having co-acting .cam surfaces Afor camming the sear means out Aof the path of the fir-ing pin, and a safety .for enga-ging said arm and detent, when in aan operative position, to lock said parts 'in `cooked position .for disarming the fuze, `said safety being retractable to release said arm and detent, to arm Lsaid fuze, said safetycomprising a stem rotatably .mounted in a wall of said housing inoperable relationship to said arm, ,one portion of said stem extending outwardly -of said Wall of said .housing and terminatingin a knob formanual rotation of said cstem, the opposite portion of saidlstem 'extend-ing inwardly of said wall of said housing -into the cavity of said housing and 'threadedly, .movably -supporting a -stop member having ya stop arm affixed thereto, said stop `member and said stop arm engaging or disengaging ,said tarm and said detent.

vBENJAMIN J. WILSON. JOHN E. STRINGER.

REFERENCES CITED The `rfollowing .references are of record in the 4le of patent:

'UNITED STATES vPASIIeTDTTS 

